CSC CSC Diagnostic Imaging & Procedures 2 — Questions and Answers
Question 1: What does a wall motion score index (WMSI) of 1.0 indicate in echocardiography?
- Severely abnormal wall motion
- Moderately reduced function
- Normal wall motion throughout (Correct answer)
- Akinesis in all segments
Correct answer: Normal wall motion throughout
A WMSI of 1.0 means all 16 or 17 segments score 1 (normal), indicating global normal wall motion.
Question 2: In cardiac MRI, late gadolinium enhancement (LGE) identifies:
- Areas of active inflammation only
- Myocardial fibrosis or scar tissue (Correct answer)
- Normal myocardial perfusion
- Valvular regurgitation volumes
Correct answer: Myocardial fibrosis or scar tissue
LGE in cardiac MRI reflects areas where gadolinium accumulates due to expanded extracellular space from fibrosis or necrosis, identifying myocardial scar.
Question 3: The modified Bernoulli equation (ΔP = 4V²) is used in echo to estimate:
- Cardiac output
- Ejection fraction
- Pressure gradients across valves or defects (Correct answer)
- Myocardial oxygen demand
Correct answer: Pressure gradients across valves or defects
The simplified Bernoulli equation converts peak Doppler velocity to pressure gradient across stenotic valves or intracardiac defects.
Question 4: Which imaging modality is considered the gold standard for assessing left ventricular volumes and ejection fraction?
- 2D transthoracic echocardiography
- Cardiac CT angiography
- Cardiac MRI (Correct answer)
- Nuclear perfusion imaging
Correct answer: Cardiac MRI
Cardiac MRI is considered the gold standard for LV volume and ejection fraction measurement due to its excellent spatial resolution and lack of geometric assumptions.
Question 5: Fractional flow reserve (FFR) is used during coronary angiography to assess:
- Degree of calcification in coronary arteries
- Hemodynamic significance of coronary stenosis (Correct answer)
- Left ventricular systolic function
- Presence of coronary artery dissection
Correct answer: Hemodynamic significance of coronary stenosis
FFR measures the pressure ratio across a stenosis to determine if a lesion is hemodynamically significant and likely to cause ischemia.
Question 6: Right heart catheterization measures all of the following EXCEPT:
- Pulmonary artery pressure
- Pulmonary capillary wedge pressure
- Cardiac output by thermodilution
- Coronary artery stenosis severity (Correct answer)
Correct answer: Coronary artery stenosis severity
Right heart catheterization measures hemodynamic pressures (PA, PCWP, RAP) and cardiac output but does not assess coronary artery anatomy — that requires coronary angiography.
CSC CSC Diagnostic Imaging & Procedures 2
What does a wall motion score index (WMSI) of 1.0 indicate in echocardiography?